1. Field of the Invention
The present invention generally relates to microfabrication and integrated circuit techniques and, in particular, to a system and method for bonding and sealing two wafers together into a single structure in order to create a vacuum chamber within the structure.
2. Related Art
In many situations, it may be desirable to form a vacuum chamber or an evacuated cavity within a microfabricated device. For example, it may be desirable to create a vacuum around complementary metal-oxide semiconductor (CMOS) components included within the device in order to increase the performance of the CMOS components.
In order to create the vacuum, a device having a chamber or cavity is initially constructed. The chamber is then evacuated and sealed so that the chamber remains evacuated. However, the process of evacuating and sealing the chamber can be difficult particularly when the device is microfabricated. As can be appreciated by one skilled in the art, the small scale of the microfabricated device makes it difficult to adequately create, evacuate and seal an opening to the chamber. In this regard, it is typically desirable to create and maintain a vacuum of at least 10.sup.-6 torr in many applications. Due to the difficulty of forming and sealing a vacuum within micromachined devices, most prior art microfabrication techniques of forming and sealing vacuum chambers are either cost prohibitive or inadequate for forming and maintaining vacuums at desirable levels.
Thus, a previously unaddressed need exists in the industry for providing a system and method for efficiently bonding and sealing wafers, particularly when the wafers are manufactured and/or processed using microfabrication techniques to form a single structure, while creating a vacuum chamber therein.